I tried using #Koala a few times on my phone and while I was able to produce music, it just seemed very cumbersome. What I really wanted was a way of easily recording multiple tracks. I'm giving #NTrackStudio a try. You can edit, add effects and beats, there's even a virtual drum kit you can play with your fingers.

n-Track Studio, a DAW which is available for #linuxaudio, now supports #dawproject files for easy project interchange between #daw (s) like #bitwigstudio, #studioone, #cubase, and now also #ntrackstudio.
https://ntrack.com/
https://github.com/bitwig/dawproject